Various kinds of objects such as facilities or the like are seen in a captured real-world image such as a photographic image of a scene. Image display apparatuses that display a captured real-world image and information relating to an object (hereinafter “object information”) seen in that captured real-world image in a single screen, in superimposed manner, are used in various fields. Such technology is called “augmented reality,” and is also referred to as “enhanced reality” and so forth. An augmented reality apparatus in which this technology is applied is useful for acquiring information on an ad-hoc basis while moving.
Technology that controls object information to be displayed by an apparatus that displays object information (hereinafter referred to simply as “information displaying apparatus”) superimposed on a captured real-world image is described in Patent Literature 1 and Patent Literature 2, for example.
FIG. 1 is a drawing showing the configuration of an information displaying apparatus described in Patent Literature 1. FIG. 2 is a drawing showing an example of a captured real-world image input by an information displaying apparatus described in Patent Literature 1. FIG. 3 is a drawing showing an example of an image in which object information is superimposed on a captured real-world image, displayed in correspondence to the input image shown in FIG. 2 by the information displaying apparatus shown in FIG. 1 (hereinafter referred to as “information superimposed image”).
As shown in FIG. 2, independent marker 12 for identifying object 11 is placed near that object in advance.
In FIG. 1, information displaying apparatus 20 has image input section 21 that receives as input a captured real-world image, marker extraction section 22 that extracts marker 12 from an input image, and marker recognition section 23 that computes the position and orientation of the extracted marker 12. In addition, information displaying apparatus 20 has related information acquisition section 24 that acquires object information relating to marker 12 in advance, model data creation section 25 that creates a graphical model data that indicates object information, and display section 26 that makes a graphical model data superimposed on side of a corresponding real-world object of an input image. As a result, image 33 shown in FIG. 3 is displayed, in which object information 32 corresponding to object 11 is displayed superimposed on captured real-world image 31 that includes an image of object 11.
Model data creation section 25 of an information displaying apparatus described in Patent Literature 1 changes the drawing position of displayed information in synchronization with a change of input image, and causes this drawing position to follow the display position of an object. Therefore, for example, an information displaying apparatus described in Patent Literature 1 can display information accurately synchronized with movement of an input image viewpoint (camera user movement) even when a user take a photo or shoot a video while the periphery of a sample is revolving.
FIG. 4 is a drawing showing the configuration of an information displaying apparatus described in Patent Literature 2. In FIG. 4, information displaying apparatus 40 has viewpoint position detection section 41 that detects a position of a user's viewpoint, display position detection section 42 that detects a position of display 47, and object position detection section 43 that detects a position of an object that is seen. Information displaying apparatus 40 also has object identification section 44 that identifies an object that is positioned on a line joining a user viewpoint and the center position of display 47, and object information search section 45 that acquires object information from a storage apparatus. In addition, information displaying apparatus 40 has image generation section 46 that selects a level of detail of displayed reference information according to the distance between a user viewpoint and display 47. As a result, when a user viewpoint comes close to the display, more detailed information is displayed.